The present invention relates generally to scanning electro-optical sensor systems, and more particularly, to ultra-wide field of view concentric scanning electro-optical sensor systems.
Most wide field of view scanning electro-optical systems have either a fisheye lens form or concentric Bouwers system. For a fisheye lens system, the overall length is at least six times the effective focal length (EFL). Consequently, the fisheye lens systems are bulky and heavy. In many cases, aspheric lenses are needed for both aberration and distortion correction. Additionally, the implementation of a scanner near the pupil plane or aperture stop is a challenging task.
Although the Bouwers system is a concentric design form, the overall length is two times the EFL. Additionally, the generic central obscuration characteristics associated with the Bouwers system often limits the F-number and the field of view coverage. Therefore, a scanner near the aperture has to be decentered with respect to the optical axis.
Accordingly, it is an objective of the present invention to provide for ultra-wide field of view concentric scanning electro-optical sensor systems that improve upon conventional fisheye lens and Bouwers type systems.